The present disclosure relates to an image forming apparatus including a mechanism of blowing air to a conveyance path on which a sheet passing through a fixing device is conveyed to a sheet discharge port.
An image forming apparatus such as a facsimile apparatus, a copy machine, a printer, or a multifunction peripheral having functions of these apparatuses includes a fixing device. The fixing device includes a heating device, and applies heat to a print sheet when the print sheet passes through the fixing device. Thus, an image is formed on the print sheet passing through the fixing device. The print sheet passing through the fixing device is discharged onto an external tray from a sheet discharge port.
In the image forming apparatus of this type, the sheet heated to a high temperature is conveyed on the conveyance path, while releasing heat, but in some cases, the sheet is discharged without a heat decrease. In this case, melted toner is not completely solidified, so that the toner might be transferred onto another sheet stacked on a tray, or the discharged print sheet might be adhered to another print sheet. On the other hand, a fixing device or an image forming apparatus that cools a sheet heated to a high temperature with a cooling fan or the like is disclosed.
However, in this fixing device, since air is vertically blown to a front surface of a print sheet, air blown to the print sheet flows toward the fixing device, resulting in that the heating device in the fixing device might also be cooled. Moreover, the print sheet is curled up from a guide by the flow of air flown into the fixing device, which hinders the conveyance of the print sheet, and in addition to this, a problem of jam of the print sheet might arise in some cases. In an image forming apparatus having a configuration of blowing air to a print sheet discharged from a sheet discharge port, air is not flown toward the fixing device. However, toner on the print sheet passing through the fixing device might be deposited onto a guide on a conveyance path. The print sheet is made of plant fiber as a main material, so that it has a property of easily retaining water. Therefore, when the print sheet is heated to a high temperature by the fixing device, water in the print sheet evaporates, and stays on the conveyance path in some cases. In this case, in the image forming apparatus having a configuration of not blowing air to the conveyance path, dew condensation occurs on the conveyance path, resulting in that the print sheet might become wet.